Date: Tue, 05 Feb 2008 01:41:08 -0500

From: Mike Miscevic
Subject: SDL and capslock/numlock

Find attached a patch against SDL-1.2.13 for check of SDL_NO_LOCK_KEYS
environment variable. This differs slightly from other patches I've seen
in that it has 3 modes:

Disable CAPS-LOCK and NUM-LOCK supression of down+up key events,
suitable for games where the player needs these keys to do more than
just toggle. A value of 1 will effect both CAPS-LOCK and NUM-LOCK. A
value of 2 will effect only CAPS-LOCK. A value of 3 will effect only
NUM-LOCK. All other values have no effect.

This works for me and has been tested on:
- Fedora 8 64-bit
- SRCRPM SDL-1.2.13-1.fc8.src.rpm
- Emeny Territory Quake Wars (ETQW), native 32-bit commercial game

--Mike Miscevic

--HG--
branch : SDL-1.2
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/branches/SDL-1.2%402732

docs/html/sdlenvvars.html

@@ -670,6 +670,21 @@ CLASS="LITERAL"
 ><P
 >If set, the linux fbcon driver will not use a mouse at all.</P
 ></DD
+><DT
+><TT
+CLASS="LITERAL"
+>SDL_NO_LOCK_KEYS</TT
+></DT
+><DD
+><P
+>Disable CAPS-LOCK and NUM-LOCK suppression of down+up key events,
+suitable for games where the player needs these keys to do more than just toggle.
+A value of 1 will effect both CAPS-LOCK and NUM-LOCK.
+A value of 2 will effect only CAPS-LOCK.
+A value of 3 will effect only NUM-LOCK.
+All other values have no effect.
+</P
+></DD
 ></DL
 ></DIV
 ></DIV

src/events/SDL_keyboard.c

@@ -48,9 +48,16 @@ struct {
 	SDL_Event evt;    /* the event we are supposed to repeat */
 } SDL_KeyRepeat;
 
+/* Global no-lock-keys support */
+static Uint8 SDL_NoLockKeys;
+
+#define SDL_NLK_CAPS 0x01
+#define SDL_NLK_NUM  0x02
+
 /* Public functions */
 int SDL_KeyboardInit(void)
 {
+	const char* env;
 	SDL_VideoDevice *video = current_video;
 	SDL_VideoDevice *this  = current_video;
 
@@ -65,6 +72,25 @@ int SDL_KeyboardInit(void)
 
 	SDL_EnableKeyRepeat(0, 0);
 
+	/* Allow environment override to disable special lock-key behavior */
+	env = getenv("SDL_NO_LOCK_KEYS");
+	SDL_NoLockKeys = 0;
+	if (env) {
+		switch (SDL_atoi(env)) {
+			case 1:
+				SDL_NoLockKeys = SDL_NLK_CAPS | SDL_NLK_NUM;
+				break;
+			case 2:
+				SDL_NoLockKeys = SDL_NLK_CAPS;
+				break;
+			case 3:
+				SDL_NoLockKeys = SDL_NLK_NUM;
+				break;
+			default:
+				break;
+		}
+	}
+
 	/* Fill in the blanks in keynames */
 	keynames[SDLK_BACKSPACE] = "backspace";
 	keynames[SDLK_TAB] = "tab";
@@ -394,12 +420,16 @@ printf("The '%s' key has been %s\n", SDL_GetKeyName(keysym->sym),
 				break;
 			case SDLK_NUMLOCK:
 				modstate ^= KMOD_NUM;
+				if ( SDL_NoLockKeys & SDL_NLK_NUM )
+					break;
 				if ( ! (modstate&KMOD_NUM) )
 					state = SDL_RELEASED;
 				keysym->mod = (SDLMod)modstate;
 				break;
 			case SDLK_CAPSLOCK:
 				modstate ^= KMOD_CAPS;
+				if ( SDL_NoLockKeys & SDL_NLK_CAPS )
+					break;
 				if ( ! (modstate&KMOD_CAPS) )
 					state = SDL_RELEASED;
 				keysym->mod = (SDLMod)modstate;
@@ -440,7 +470,13 @@ printf("The '%s' key has been %s\n", SDL_GetKeyName(keysym->sym),
 			case SDLK_UNKNOWN:
 				break;
 			case SDLK_NUMLOCK:
+				if ( SDL_NoLockKeys & SDL_NLK_NUM )
+					break;
+				/* Only send keydown events */
+				return(0);
 			case SDLK_CAPSLOCK:
+				if ( SDL_NoLockKeys & SDL_NLK_CAPS )
+					break;
 				/* Only send keydown events */
 				return(0);
 			case SDLK_LCTRL: